Mauger made his All Black debut against Ireland in 2001, notching a try. A composed centre and sometime fly-half, Mauger's excellent kicking game and intelligent reading of a backline made him a vital part of New Zealand's armoury during their successful period at the turn of the Millennium. He played his provincial rugby for Canterbury and was a regular in Super Rugby for the Crusaders. Having been controversially overlooked for their 2007 Rugby World Cup quarter-final defeat to France in Cardiff, in favour of Luke McAlister, Mauger joined Guinness Premiership side Leicester Tigers, retiring in 2010 due to a persistent back injury. His brother, Nathan, played two games for the All Blacks in 2001.